A conventional light curing device is adapted to emit light on a hand or foot of a user applied with a light curable product, such as gel nail polish. The conventional light curing device however lacks an indicator for showing duration of the light curing process or state of the conventional light curing device, such as whether or not the device is activated. Furthermore, the conventional light curing device is not capable of emitting curing light with different wavelengths for different types of the gel nail polish or for different thicknesses of the gel nail polish applied to nails.